Probably using BBAlerts app...it allows you to change the colour of your indicators to certain colours.
Usually Blue is for bluetooth ie when your using bluetooth.
I turned mine off though, talk about irritating, like telling you that you have a message but it's brighter and keeps flashing while your bluetooth is on. I have on of the motorola earpieces that the boom closes so if I'm not wearing it it's off.
Superfluous blinking LEDs are a pox on the electronics industry. The last thing I need is a bright blue or green blinking parrot squawking, "everything's normal! Everything's normal!..."
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Just turning on bluetooth will not activate the blue led. The blue led only flashes when connected to another device via bluetooth. I find this a very handy feature. It's a good reminder when I'm away from my vehicle yet still within bluetooth range that it's still connected.
Color light app its decent but it helps drain the battery. You can choose a few different colors (blue, green, red, etc.) and have flash, solid or disco(all colors changing). Good for only $7.
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